The present disclosure relates to a switchboard and, more specifically, to a transformer position adjustment preventing device of a switchboard by which the position adjustment of a transformer disposed in a transformer chamber can be prevented.
Generally, a circuit breaker is an electricity protection device for protecting a load device and a cable route from a fault current during an accident such as a short circuit or earth fault generated on an electric circuit.
Depending on a type of an extinguishing medium, the circuit breaker may be classified into an oil circuit breaker using oil as an extinguishing medium, a gas circuit breaker using a sulfur hexafluoride (SF6) gas which is an inert gas, an air circuit breaker using air as an extinguishing medium, a circuit breaker using magnetism, and a vacuum circuit breaker using vacuum dielectric strength.
Currently, most of electric power device products use a sulfur hexafluoride gas having excellent arc extinguishing and insulating property, but the sulfur hexafluoride gas causes a greenhouse effect of 23,900 times more than carbon dioxide, so that it is being globally restricted to use the sulfur hexafluoride gas.
Environmentally-friendly electric power device products that can replace the sulfur hexafluoride gas are actively developed in Korea, and a demand for a vacuum circuit breaker as one of the environmentally-friendly electric power device products is remarkably increasing.
The vacuum circuit breaker mainly plays a role of controlling electricity transportation and protecting an electric power system, has a large breaking capacity, exhibits high reliability and stability, and can be disposed even in a small installation space, so that the applied range of the vacuum circuit breaker is extending from a medium voltage to a high voltage.
The vacuum circuit breaker is installed along with a switchboard for accommodating and managing several sorts of electrical instruments including a circuit breaker therein so as to operate or control a power plant and a substation and operate a motor, and the vacuum circuit breaker is used as being accommodated in a cradle fixed on the switchboard.
The switchboard equipped with the vacuum circuit breaker has a transformer chamber disposed below the cradle and a transformer installed inside the transformer chamber, and the transformer is seated on a transformer truck as similar to the circuit breaker and is then moved to a test position for maintenance and an operation position for transformation by coming in contact with a load terminal.
FIG. 1 is a perspective view illustrating the inside of a related art switchboard.
As illustrated in FIG. 1, a switchboard 10 equipped with a vacuum circuit breaker includes a vacuum circuit breaker chamber 11 provided with a vacuum circuit breaker 12, and a transformer chamber 13 disposed below the vacuum circuit breaker chamber 11 and provided with a transformer 14, wherein the transformer chamber 13 is able to be opened using a transformer door 17.
The vacuum circuit breaker chamber 11 is provided with the vacuum circuit breaker 12. In the transformer chamber 13, the transformer 14 seated on a transformer truck 16 is moved therein to a test position or an operation position, wherein a power fuse 18 is disposed over the transformer 14 and a ground switch 15 is disposed on the rear surface of the switchboard 10.
Like above, in the related art switchboard, when the power fuse 18 blows due to the occurrence of a fault voltage, the power fuse 18 should be replaced. Here, the power fuse 18 is replaced after the transformer door 17 is opened to withdraw the transformer truck 16 irrespective of whether the ground switch 15 is at an input position or an open position.
However, even when the transformer 14 is moved to a test position after a fault voltage occurs, a residual voltage remains in the transformer 14 and load terminal. Therefore, maintenance should be performed after the remaining residual voltage is removed by allowing the ground switch 15 to be at the input position, however, the transformer door 17 may be opened without a stabilizer while the ground switch 15 is not at the input position, thereby causing a problem in that a worker has a great danger of encountering electric shock while the residual voltage remains in the transformer chamber 13.